What I find very strange is why the Bluesound App continues to have access to the MQA files on Tidal, whereas Roon Does not ???
Not so. Yesterday, I listened to multiple MQA identified tracks via Roon/Tidal to my Meridian Prime.
There are still loads of 44/16 (CD mastered) MQA albums available via TIDAL Max, presumably because the CD master is all that is available and there is no corresponding "HiRes" master. However, most of the MQA with original sample rate > 44k has been replaced and you'll have a hard time finding 96k and 192k ORFs MQA.